Draw mechanism for straight-bar knitting machines



3 Sheets-Sheet 1 B- F. SWANWICK ETA]- QN .u@ ,2 ME

DRAW MECHANISM FOR STRAIGHT-BAR KNITTING MACHINES Filed June 5, 1968Sept. 15, 1970 '3 Sheets-Sheet 2 W 4 mm a II g zw/ m mm Sept- 1970 B. F.SWANWICK ElAL DRAW MECHANISM FOR STRAIGHT-BAR KNITTING MACHINES FiledJune 3. 1968 Sept. 15, 1970 B. F. SWANWICK ETAL 7 3,528,266

DRAW MECHANISM FOR STRAIGHT-BAR KNITTING MACHINES EiledJune 5, 1.968 3Sheets-:Sheet 5 618 63633163, 25a 38 64 $259 67a 531, rv

United States Patent 3,528,266 DRAW MECHANISM FOR STRAIGHT-BAR KNITTINGMACHINES Barry Frederick Swanwick, Melton Mowbray, and Ernest West,Kirkby-in-Ashfield, England, assignors to S. A. Monk(Sntton-in-Ashfield) Limited, Sutton-in-Ashfield, Nottingham, England, aBritish company Filed June 3, 1968, Ser. No. 733,913 Claims priority,application Great Britain, June 14, 1967, 27,405 67 Int. Cl. D04b /64US. Cl. 66--126 9 Claims ABSTRACT OF THE DISCLOSURE A draw motion for astraight-bar knitting machine. The cross shaft and the draw camcontinuously rotate and the draw lever thus continuously oscillates toreciprocate the main rack irrespective of whether machine is knitting orfashioning. Means are included to transmit a drive from this rack toyarn carrier and slur cam drive systems. Between the rack and the saiddrive systems are provided automatically operable means to disconnectthe drivetransmitting means from the rack, prior to fashioning, and toreestablish the connection between the drive-transmitting means and therack upon resumption of knitting.

This invention appertains to a draw motion for a multihead straight-barknitting machine of the Cottons patent or similar type forfully-fashioned outerwear manufacture.

The invention, moreover, is concerned particularly with a draw motion ofthe kind in which a rotary draw cam, operating on trucks mounted on apitman lever to cause to and fro movement of the latter, is used toeffect, through the medium of the pitman lever, oscillatory movements ofa swinging type main draw lever which is adapted to drive andreciprocate a main rack from which are in turn driven slur and yarncarrier drive systems.

In a machine of the type concerned, the slut cams, one to each head ordivision, are mounted on slur cam boxes fastened to a slur rail whichextends along the length of the machine. The slur cams are driven acrossthe sinker head through the medium of a tie bar in turn driven from themain rack through rack and pinion mechanism. The said rail, in the caseof a machine fitted, as is primarily the intention, with a variabledraw, is mounted on small levers to enable the said rail to have arocking action to remove the slur cams from the rear of the sinker headduring the knitting part of the loop forming cycle.

Although a straight-bar knitting machine to which the invention isapplied may have a friction type of yarn carrier drive including rods,it is mainly the intention that it shall have a chain type carrier drivearranged to provide a controlled lead of the yarn carriers over the slurcams on virtually all knitting widths.

The invention accordingly has reference exclusively to a multi-headstraight-bar knitting machine of the type specified including fashioningmechanism for shaping knitted fabric or garment blanks produced at thedivisions as a consequence of widening or/ and narrowing by 100ptransference to increase the number of wales, such increase or decreasebeing brought about by increasing or decreasing the number of operativeneedles at either or both selvedges without alteration to the characterof the stitch.

3,528,266 Patented Sept. 15,, 1970 As well known to those acquaintedwith the art concerned, a straight-bar knitting machine of the typereferred to is provided with a continuously rotatable main cam shaftfrom and by which the various machine motions are respectively derivedand controlled. From this main cam shaft is driven, usually through themedium of 2:1 bevel gearing, a cross shaft upon which is secured theaforementioned rotary draw cam.

The said cam shaft is adapted to be axially shifted bodily by alongitudinal shogging motion, from a normal position during which yarnsinking and knitting takes place to another position in which fashioningcams are introduced to the various motions for garment shaping and viceversa. The mechanism employed for effecting these shogging motions isknown as the cam shaft shogging motion and will be hereinafter describedbecause it is used in the performance of the present invention.

Each time the cam shaft is shogged into its fashioning position, andduring one revolution thereof, the yarn carriers and the slur cams arerequired to remain stationary at one side or the other of the knittingwidths. To this end it is necessary to disconnect the common drive fromthe main draw lever and main rack to the yarn carriers and the slur camswhilst fashioning takes place.

Now heretofore in a conventional machine this has been achieved bycausing the previously mentioned cross shaft, the draw cam, the pitmanlever and the main draw lever (together with the short auxiliary drawlever in the case of a variable draw motion) to remain stationary. Thisinvolved a disconnection of the drive, caused by shogging thecontinuously rotating cam shaft, from a bevel pinion on the latter to abevel wheel secured upon the cross shaft. The said disconnection of thedrive was effected, in fact, by disengagement of a driving dog from thebevel pinion. Thus, whenever the cam shaft returned from its fashioningposition to its knitting position the driving dog re-engaged the bevelpinion and, by impact, caused the cross shaft the draw cam to rotateagain and so I e-established the drive to the yarn carriers and slurcams. As will be readily appreciated, with the increasingly heavymachines now made and the higher speeds now possible this impact is mostundesirable as it tends to create excessive stresses and mechanicalfailures.

The object of the present invention is to provide, in a multi-headstraight-bar knitting machine, an improved draw motion of the kindherein referred to designed to obviate any necessity to disconnect, forfashioning, the drive from the continuously rotatable cam shaft to thecross shaft, thereby eliminating all shock loads betweendrive-transmitting components, whilst at the same time retainingconventional means for synchronising the direction and timing of theyarn carrier and slur draw drive systems.

According to this invention the cross shaft and the draw cam of theimproved draw motion continuously rotate and the main draw lever thuscontinuously oscillates to reciprocate the main rack irrespective ofwhether the machine is knitting or fashioning, and means are providedbetween the continuously reciprocable main rack and the carrier and slurcam drive systems for automatically disconnecting the said systems fromthe main rack, prior to fashioning, and for re-establishing theconnection of the systems to the main rack upon a resumption ofknitting.

An important feature of the improved arrangement is 3 that the yarncarriers and the slur cams can be picked up upon a resumption ofknitting from those side edges of the garment blanks at which they weredeposited prior to fashioning irrespective of the direction ofoscillation of the main draw lever.

In a convenient embodiment of the invention, the main rack constitutesone of two continuously and contrareciprocating bars arranged to bedriven by or from the main draw lever, and automatically actuatablelatch means are provided to effect a drive-transmitting connectionbetween these two bars and a further reciprocable member from which theyarn carrier and slur cam drives are controlled during knittingoperations. The said latch means are essentially also appropriatelyoperable to effect disconnection of the reciprocable member from therelevant one of the two contra-reciprocating bars prior to a fashioningoperation.

Advantageously, these latch means may be arranged to be actuated by acam on the continuously rotatable main cam shaft of the machine, throughthe medium of any suitable intermediate linkage, this cam being broughtinto co-operative relationship with the linkage each time the said camshaft is shifted longitudinally by the cam shaft shogging motion for afashioning operation.

The contra-reciprocating bars may be combined with opposed racks havinginterposed therebetween an idler pinion whereby the racks have impartedthereto identical but opposite traverses.

As to the aforesaid reciprocable member from which the carrier and slurcam drives are controlled during knitting, this may conveniently consistof a third rack bar which, in effect, takes the place of the main rackin regard to its relationship to the carrier and slur cam drives.

Thus, as will be appreciated, this third rack bar, and hence also thecarrier and slur drives may, by the simple automatic actuation oflatches, be caused to remain quiescent whilst the cross shaft, the drawcam and the associated levers continue to operate.

In order that the invention may be more clearly understood and readilycarried into practical effect, a specific constructional example thereofapplied to a variable draw motion will now be described with referenceto the accompanying drawings, wherein,

FIG. 1 is a fragmentary plan view illustrating the existingdrive-transmitting arrangement between the continuously rotatable maincam shaft and the cross shaft of such a variable draw motion, ie theconventional arrangement wherein the cross shaft and hence also the vrotary draw cam are stopped from rotating during fashioning,

FIG. 2 is a view similar to FIG. 1 depicting, by way of comparison, theimproved drive-transmitting arrangement of the present invention whereinthe drive from the main cam shaft to the cross shaft is neverinterrupted, thereby enabling the draw cam to rotate both when the maincam shaft is in the fashioning as well as in the knitting position, thisfigure also showing the cam shaft shogging motion common to the existingand the improved arrangements,

FIG. 3 is a general perspective view, from the front of the machine, ofso much of the improved variable draw motion as is necessary to show theaforementioned two continuously and contra-reciprocating bars and themeans by which they are driven from the main draw lever, and

FIG. 4 is another perspective view, also from the front, illustratingextensions of the said two continuously and contra-reciprocating bars,and the automatically actuable latch means whereby these bars arealternately connected to a third reciprocable bar from which the yarncarrier and slur cam drives are controlled during knitting cycles.

Like parts are designated by similar reference characters throughout thedrawings.

Referring to FIG. 1, it will be seen that rotation of the main cam shaft10* causes rotation of the bevel pinion 11 rigid therewith and hencealso of the bevel gear 12 and the cross shaft 13 to which the said bevelgear is secured. It is on the cross shaft 13 that the rotary draw cam 14of the illustrated variable draw motion (see FIG. 3) is rigidly securedso as to rotate together therewith. The bevel pinion 11 has integrallycombined therewith the suitably slotted female member 15 of a dog clutchDC. The slot 15a in the member 15 is adapted to receive aspring-influenced driving dog 16 protruding from a clutch block 16a onthe main cam shaft 10.

Now in the existing arrangement, the cross shaft 13 and the draw cam 14rotate only during knittingat which time the driving dog 16 is engagedin the slot in the female member 15. However, during fashioning,initiated by an axial shogging movement of the main cam shaft 10 to theright, effected by the cam shaft shogging motion SM illustrated withinthe chain-line rectangle in FIG. 2, the driving dog 16 is, in theexisting arrangement, disengaged from the female member 15, as shown inFIG. 1, thereby allowing the cross shaft 13 and the draw cam 14 to bestationary, with the cam shaft 10 continuing to rotate.

But in the proposed improved draw arrangement (a part of which isillustrated in FIG. 2), the dog clutch is so designed and arranged thatthe driving dog 16, which does not in this case require to bespring-influenced, and the female member 15 are permanently engaged.This, of course, results in the drive from the main cam shaft 10 to thecross shaft 13 never being disconnected. That is to say, even when thecam shaft 10 is shogged to the right by the shogging motion SM, forfashioning, the driving dog 16 will remain in the slot 15a in the femalemember 15, and the cross shaft 13, instead of being stopped asheretofore, will continue to rotate.

It will be convenient here briefly to describe the cam shaft shoggingmotion SM which is of quite conventional form and, as previouslymentioned, common to both the existing and the improved arrangementsshown in FIGS. 1 and 2 respectively.

A selection obtained from the fashioning frequency control unit (notshown) results in the removal of a latch 17 from a position between atruck housing 18 and an enlarged portion 19a of a truck shaft 19 whereit holds a shog truck 20 in the knitting position indicated in chainlines in FIG. 2. With the retaining latch 17 removed, however, the shogtruck 20 is moved forward to the full line position to be presented to ashog cam 21 under the action of a tension spring 22. As the main camshaft 10 revolves, the shog truck 20 acts on the shog cam 21 to move thesaid cam shaft axially to the right from its normal knitting position toits fashioning position. By this shogging movement the fashioning camsare introduced to the various motions. But as the cam shaft 10 revolvesfor the transfer of loops, the selection for fashioning is cancelled andthe shog truck 20 returned to the knitting position by a shog releasecam 23. This shog release cam 23 acts on a roller 24 mounted at the endof a slide 25 attached to the shog truck assembly to return the shogtruck 20 to the knitting position against the action of the spring 22.As the shog truck is withdrawn, the retaining latch 17 is re-introducedbetween the truck housing 18 and the portion 19a of the truck shaft 19to hold the shog truck in the knitting position. In this position theshog truck 20 is presented to a return cam 26 which returns the camshaft 10 to the knitting position at the end of the fashioning cycle.

In general terms, the illustrated variable draw motion is basically ofthe standard form wherein the thrust applied to a main draw lever 27 issupplied by the draw cam 14 which converts rotary motion of the main camshaft 10 into the required lateral movement. Viewing FIG. 3, it will beseen that the said rotary draw cam 14 operates on and between two trucks28 and 29 mounted on a pitman lever 30. The latter is caused, by theaction of the cam and the trucks, to oscillate to and fro between ashort draw lever 31 and a supporting lever 32 between the fixed throw ofthe pitman lever and the variable throw of the main draw lever 27. Theconnection between the levers 27 and 31 is obtained by a connecting pin33 which connects together two sliding die blocks operating respectivelyin the usual slot in the lever 31 and on the conventional lead screw(not shown) in the main draw lever 27.

The drive from the main draw lever 27 to the main rack 34 of thevariable draw motion is through a pin 35 and an associated die block at36 operating in a slot 37 cut in the top of the said draw lever 27. Inall other respects, including the manner in which the draw isautomatically varied upon variation of the knitting width, thecomponents of variable draw motion between the cam 14 and the main rack34 are conventional and accordingly do not require any furtherdescription.

However, the illustrated draw motion differs from a conventional drawmotion in that, in accordance with the present invention, there isarranged directly above the bar constituting the main rack 34 a secondbar 38 provided with a toothed rack 39. The two bars 34 and 38 arehorizontally disposed and spaced apart parallel to one another. An idlerpinion 40 interposed between and arranged in mesh with the two opposedseries of rack teeth 34a and 39a serves to drive the second bar from themain rack bar 34 so that the two have imparted to them identical butopposite traverses. The two bars 34 and 38 can, therefore, be aptlydescribed as two continuously and contra-reciprocating bars arranged tobe driven respectively by and from the main draw lever 27.

A third horizontal and reciprocable bar 41, provided with a toothed rack42, is mounted in front of the main rack bar 34. Arranged in mesh withthe rack teeth 42a of this third bar 41 is a pinion 43 which is rigidwith a turnable shaft 44 disposed parallel with respect to the crossshaft 13. The arrangement is accordingly such that any traverse impartedto the third bar 41 in either direction from the continuouslycontra-reciprocating bars 34 and 38 by means presently to be described,will effect turning movements of the shaft 44. Merely for con 'venience,the aforementioned idler pinion 40 is also mounted on, but is, ofcourse, rotatable independently of, the shaft 44.

Mounted on a forward extension of the shaft 44 so as to rotate togethertherewith are chain sprockets 45 or any other appropriate drive media tothe carrier drive system of the machine, and also a slur drive gear 46arranged to mesh with teeth 47a of e rack 47 combined with the slide bar48. Thus, the idler pinion 40, the pinion 43 and the slur drive gear 46are all co-axially arranged.

The conventional slur rail 49, upon which are mounted boxes such as 50incorporating the slur cams, one of which is designated by the numeral51, is adapted to be reciprocated from the slide bar 48 to drive theslur cams to and fro across the knitting width. For this purpose, theslide bar 48 is fitted wtih a slur drive bolt 52 arranged to engage in asuitably dimensioned recess 53a in a drive component 53 attached to theslur rail 49. The distance a slur cam lags behind the relevant yarncarrier is indicated at d in FIG. 3.

Extensions of the two continuously and contra-reciprocating bars 34 and38 are shown in FIG. 4 in which figure means for connecting these twobars alternately to the third reciprocable bar 41 from which, as alreadyexplained, the yarn carrier and slur cam drives are controlled duringknitting cycles.

The said latch means, as will be seen, comprise an upwardly directedspring-influenced latch 54 slidable vertically in a box 55 attached tothe bar 34 (main rack), and a downwardly directed similar latch 56slidably mounted in a like box 55 attached to the oppositelyreciprocable bar 38. The two latches 54 and 56 extend at right angles tothe contra-reciprocating bars 34 and 38, the latch 54 on the lower bar34 being spring-loaded in a vertically upward direction and that, 56, onthe upper bar 38 being similarly spring-loaded but in a verticallydownward direction. As will be appreciated, as the lower bar 34 iscaused to reciprocate by the oscillating main draw lever 27 and hencethe upper bar 38 is contrareciprocated through the medium of the idlerpinion 40, the two latches 54 and 56 will repeatedly pass one another inopposite directions. These latches will, in fact, pass one anotherduring each revolution of the cam shaft 10 since the cross shaft 13continuously rotates and the main draw lever continuously oscillates.

On the third reciprocable bar 41 is fixedly attached a driving block 57which is vertically slotted at 57a suchwise as to be capable ofreceiving either the latch 54 from below or the latch 56 from above. Itwill be noted that not only are the sides of the latches chamfered atthe leading ends thereof, but also the upper and lower edges of thehorizontal portion 57b of the driving block 57 are chamfered tofacilitate engagement of a latch in the slot 57a.

For controlling the engagement of the latches 54 and 56 into, and theirwithdrawal from, the slot 57aalternately-there is provided a horizontalrod 58 which is carried between the forward ends of arms 59a of suitablyspaced levers 59. The rod 58 is for action upon small rollers R1 and R2carried by the latches 54 and 56 re spectively. The levers 59 arefulcrummed at 60 midway between their opposite ends in fixed brackets61. The forward ends of the arms 59b of the levers 59 are connected by afurther horizontal rod 62 which is parallel to the rod 58 and isarranged to be acted upon by a suita'bly contoured edge cam 63. This camis adapted to be turned intermittently about the axis of a carrier shaft64 which is mounted in upwardly directed extension arms 61a of thebrackets 61. The cam 63 has thereon four convex rises 63a spaced apartand four intervening concave depressions 63b. Thus, as the said cam isintermittently rotated, the rod 62 will be alternately depressed andallowed to rise as a consequence of which the rod 58 will be alternatelyraised and lowered to actuate and control the latches 45 and 56. Therollers R1 and R2 are, of course, both held permanently in contact withthe rod 58 by the latch springs S1 and S2 respectively. That is to say,the roller R1 is always held up against the underside of the rod 58under the action of the spring S1, whereas the roller R2 is at all timesheld down on to the upper side of the same rod under the action of thespring S2the two springs acting upwardly and downwardly respectively.

The cam 63 has combined with it at one side thereof a ratchet wheel 65,and for indexing this wheel to turn the said cam there is provided aspring-influenced pawl which is pivotally mounted at 66 upon a rockablelever 67. The latter is connected, by a link 68, with one arm 69a of atwo-armed lever 69 which is arranged to fulcrum about a fixed shaft 70.The other arm 69b of the lever 69 is furnished with a cam follower 71.The main cam shaft 10 has thereon a cam 72 which, whenever the saidshaft is shogged to the right into the fashioning position by the camshaft shogging motion SM is moved into line with the cam follower 71.Conversely, whenever the cam shaft 10 is shogged back leftwards into theknitting position, the cam 72 will be displaced out of line with the camfollower 71.

The operation of the herein described improved draw motion will now bedescribed. Assume first that the machine is knitting plain courses andthat the latch 54 is en gaged in the slot 57a in the draving block 57.In these conditions, the reciprocating bar 34 (main rack) imparts anidentical reciprocating motion to the third bar 41 so that the yarncarriers and the slur cams correspondingly reciprocate from side to sidesimultaneously with the os cillatory movements of the main draw lever27. But if the machine is required to fashion, the main cam shaft 10 isshogged laterally to the right and the cam 72 is thereby brought intoline with the cam follower 71. At this instant, the latch 54 on the bar34 and also the driving block 57 on the third bar 41 are both at the endof a traverse. The cam 72, acting on the follower 71, now indexes theratchet wheel 65 as a consequence of which the cam 63 is turned through45 from a position in which a rise 63a thereon is in contact with therod 62 to another position in which a depression 63b in the cam isopposed to the said rod. The rod 62 accordingly moves upwards and therod 58 downwards-see-saw fashion. The result of this is that the latch54 is depressed against the action of its spring S1 and therebydisengaged vertically downwards from the slot 57a in the driving block57. At the same time the latch 56 is permitted to move verticallydownwards under the action of its spring S2 so as to be in a suitableposition for engaging in the slot 57a. The disengagement of the latch 54from the driving block 57 disconnects the third bar 41 so that itremains quiescent and imparts no motion to the yarn carrier and slur camdrives during fashioning. Meanwhile, the draw cam 14 continues to rotateand the draw lever 27 proceeds with its traverse as fashioning takesplace. By the time the draw lever has completed its traverse, the upperreciprocating bar 38 will have traversed in the reverse direction until,at the completion of the fashioning course, the latch 56 engagesdownwardly in the slot 57a in the driving block 57 under the influenceof the spring loading. Thus, during the next draw, the bar 38 willtransmit motion to the third bar 41 but this time in the oppositedirection with respect to the draw lever traverse. Accordingly, an idledraw during fashioning, i.e. a draw as a consequence of which no motionis imparted to the yarn carriers and slur cams, is brought about byindexing of the ratchet wheel 65 and a one eighth turn of the cam 63initiated by shogging of the main cam shaft 10 to the right.

Prior to the next fashioning course, latch 56 will be in engagement withthe block 57, and so the purpose of the next operation of the linkage67, 68 and 69 must be to effect disengagement of the latch 56 from thesaid block and to release the latch 54 for subsequent engagement in theslot in the block. This is achieved as a consequence of the nextindexing movement of the ratchet wheel 65 which causes the cam 63 to beturned through a further 45 from the position in which a cam depression63b is opposed to the rod 62 to another position in which a rise 63a onthe cam is in contact with the said rod. As a result, the rod 62 ismoved downwards and the rod 58 upwards so that the latch 56 will bemoved up and withdrawn from the block 57 and the latch 54 permitted tomove up so as to bein a position for engaging in the slot 57a.

We claim:

1. In a multi-head straight-bar knitting machine having a main camshaft; fashioning mechanism adapted to be brought into operation by alongitudinal movement of the said main cam shaft; a cam shaft shoggingunit for so moving the cam shaft; a yarn carrier drive system and a slurcam drive system, a draw motion comprising, in combination, a crossshaft driven from said main cam shaft; a rotary draw cam on said crossshaft; a pitman lever having thereon spaced trucks between which thedraw cam is located for action thereupon to move the pitman lever to andfro; a pivoted draw lever which is oscillated from the said pitmanlever; a main rack which is connected to the draw lever and is thusreciprocated therefrom and drive-transmitting means between the saidrack and the aforesaid yarn carrier and slur cam drive systems, whereinthe improvement comprises the provision, between the reciprocable rackand the yarn carrier and slur cam drive systems, means automaticallyoperable to disconnect the drive-transmitting means from the rack priorto fashioning and to re-establish the connection between saiddrive-transmitting means and the rack upon a resumption of knitting,wherein, when the ma 8 chine is in operation the cross shaft and thedraw cam continuously oscillates to continuously reciprocate the rackirrespective of whether the machine is knitting or fashioning.

2. A draw motion according to claim 1, wherein the main rack constitutesthe first of two parallel bars the first bar being so driven from thesecond that the two traverse to the same extents but in respectivelyopposite directions, and automatically actuatable means are pro: videdto effect a drive-transmitting connection between one or the other ofthe said two bars and a third reciprocable member from which the yarncarrier and the slur cam drives are controlled during knittingoperations, the said means being operable to effect disconnection of thethird reciprocable member from the relevant one of the twocontra-reciprocable bars prior to each fashioning operation, whereby theyarn carriers and the slur cams can be picked up upon a resumption ofknitting from those side edges of blanks being produced at which theywere deposited prior to fashioning irrespective of the direction ofoscillation of the draw lever.

3. A draw motion according to claim 2, wherein the said automaticallyactuatable means consist of two latches which are respectively carriedby and are traversible together with the two contra-reciprocable bars,each of these latches being adapted for engagement at an appropiratetime in a driving component carried by the third reciprocable member andone of them being automatically withdrawn from, whilst the other isreleased for subsequent engagement in, the driving component,immediately prior to each fashioning operation, whereby during thelatter the third reciprocable member remains quiescent.

4. A draw motion according to claim 3, wherein the latches are arrangedto be actuated by a cam on the continuously rotatable main cam shaft ofthe machine through the medium of intermediate linkage, this cam beingbrought into co-operative relationship with the said linkage each timethe cam shaft is shifted longitudinally by the cam shaft shogging motionfor a fashioning operation and disengaged from the linkage whenever thesaid cam shaft is shogged in the opposite direction upon a resumption ofknitting.

5. A draw motion according to claim 4, wherein the two latches extend atright angles to the contra-reciprocable bars, one of the latches beingspring-loaded in a vertically upward direction and the other beingsimilarly spring-loaded but in a vertically downward direction.

6. A draw motion according to claim 4, wherein the intermediate linkageincludes a horizontal rod which is arranged for permanent engagementwith rollers on the latches this rod being movable up and down byoperating means under the control of the cam on the main cam shaft, thearrangement being such that whether the rod is moved up or down, one ofthe latches will be withdrawn downwardly from a vertical slot in theaforementioned driving component carried by the third reciprocablememher while the other latch is released for subsequent upwardengagement into this slot, or vice versa.

7. A draw motion according to claim 6, wherein the horizontal rod isconnected by rocking levers to a second rod parallel with the first sothat as the second rod is pushed down the first rod will move up, andvice versa, and the operating means consist of a suitably profiled camwhich is arranged in contact with the second rod and is adapted to beracked round by indexing means operable from the cam on the main camshaft.

8. A draw motion according to claim 2, wherein both of thecontra-reciprocable bars are provided with rack teeth thereby providingopposed racks, and wherein there is interposed between and in mesh withsaid racks an idler pinion.

9. A draw motion according to claim 2, wherein the third reciprocablemember consists of a rack bar arranged in mesh with a pinion securedupon a shaft upon which are also mounted carrier drive sprockets and aslur drive 9 10 gear in mesh with a rack on a bar from which the slur2,872,798 2/1959 Matthews et a1. 66-126 XR cams derive their movements.2,907,194 10/1959 Anke 66126 References Cited 2,912,840 11/1959 Cobert66130 XR UNITED STATES PATENTS 5 RONALD FELDBAUM, Primary Examiner2,309,091 1/1943 Beers 66-130 US. Cl. X.R. 2,366,340 1/1945 Lambach66-126 XR 66-82 2,705,879 4/1955 Scheller 66126

